Liquid piston internal combustion pump for liquids



Sept. 29, 1931. s. P. CHRISTIE 1,825,507

LIQUID PISTON INTERNAL COMBUSTION PUMP FOR LIQUIDS Filed July 8, 1930 low pressure) bya main transfer, valve sub Patented Sept. 29, 1931 7 UNITED STATES P TENT orricafi STANL Y rnzacr ormrsrin, oF'LonDoNQnneLAND ,LIQuiD iston inrnnimn coivrnusrron BUMP FOR mourns Application filed July a, 1920, Serial No. 466,552, andiirGreat Britain Jul 29, 1929.

This invention is for improvements in or relating to liquid piston internal combustion gas pumps of the type in which the combus tible charge is introduced to: the working cylinder during the upward or return stroke of the liquid piston. T i I 'In such pumps the gases developed by ignition of a fuel charge within a vertical combustionchamber are allowed to, act di- 1151 rectly upon the surface of a column of liquid therein and thereby to discharge saidliquid under pressure into the play-pipe of the pump i. e. into a conduit communicating with the lower end of the combustion chamber. Compression of the combustible charge is effected by the return stroke of the liquid column. Such devices'may be used either in the form of'pumps'tor raising liquids or as'im'pelling devices to efiect propulsion of mi navigable vessels. In the latter case the dis charge from the play-pipe is directed from the vessel onto or below. the surface of' the water in'which the vessel travels. It will beimderstoo'd that the term pumps is used -he1'ein.to cover bothof the above forms.

It has been found to bedesirable,v tore ample, inv suchipumps which operate upon two-stroke cycle, to introduce the combustible charge immediately above the surface of therisin'g liquid column in order thatjno unburnt gas shall be swept. up

through the exhaust valve.

My prior British patentspecification Nof 288,696 describes a two-stroke liquidpiston charge is compressed by a liquid column in a gasintakechamber,and-is passed therefrom in two charges each at a different pressure to the combustion chamber, first (at a valve is forced elf its seat when the pressure of the residual gastrapped in the intake chamber upon the closing of the main transfer valve reaches a certain value.-

internal Hc'ombusiion pump in :which' the piston internal combustion pump of the type specified in which the fuel is introduced wholly or in part during the upstroke of the liquid column, characterized by-t'he provision within the pump chamber of guide mech- 5 anism so arranged and so operable on the upstroke of the liquid column as tocOnline' the distribution of the charge to a zone which is-immediately above and which rises bodily with the surface of the liquid column. 00:

Preferably said guide mechanism is operable by the impact of the risin liquid column or byvthe buoyancy of floats or the like actedupon by the risingcolumn.

, Conveniently the pump maybe provided 65v with a series of inlet valves spaced apart one above the other in such manner that as the rising liquid column closes or seals each valvein turn it causes the valve immediately aboveto open; a f a In onepreferred form, a pumpis pro vided with a series of butterfly valves spaced apart one fabovethe other,"" with each of which-valves is associated a paddle or float, the weight of which tends to maintain-thevalveclosed; butwhih is'arranged to be liftedby the risinggliquid column'to open the valve, eaoh lpaddle or float being lifted in turn; The arrangement maybe such that the rising liquid columnwill seal each valve in turn by submerging it. i r

,Two constructionsaccording to this invention will now be described in detail by wayofqe'xample with reference to the accompanying drawings, in which a,

Figure 1 is asection through the standpipefor working cylinder of a liquid pistoninternal combustion pump provided with inlet valves according to this invention, and V Figure 2 isja similar section showing a modified arrangement of valves.

Throughout this description like refer ence numeralsindicate like parts.

The pump comprises a sand-pipe 10 pro-' vided with a main inlet'valve indicated gen erally by the numeral ll, and an exhaust valve 12, the details of which are-not relei vantto the present description and are not 1 The-present invention, provideswa liquid shown.- The sand -pipe is provided with O0 a central vertical partition 13 extending nearly to the top of the working cylinder, the combustible charge being introduced into the stand-pipe on one side of this partition and the exhaust gases being expelled or withdrawn on the other side.

The present invention is concerned only. with the admission and distribution of the combustible charge, but for the sake of clearness a brief description will be given of the general operation of the pump as a whole.

The fuel ignition chamber is constituted by the upper end 30 of the stand pipe 10, this chamber being provided with sparking plugs in the usual way. The lower end of the stand pipe 10 delivers to a playp1pe. Assuming a combustible charge to be compressed in the upper end of the pipe 10, ignition is effected by the plugs in the ordinary manner and the gases developed thereby expand driving out the liquid from the lower end of the stand pipe. 011 reduction in pressure within the stand pipe, due to the expulsion of the liquid therefrom, a fresh charge is admitted on the right hand side of the partition 13 (in a manner to be hereinafter described) and on the return flow of the liquid column the burnt gases are discharged through the exhaust valve 12 and the fresh charge is compressed. The same series of operations are then repeated. The return flow of liquid to effect the scavenging and compression stroke of the pump may be brought about in any of the ways common in this class of apparatus. For example, the lower end of the stand pipe 10 may deliver wholly or partially into an air or gas reservoir, the compression built up therein during the expulsion stroke being employed to effect the return flow of liquid. The main inlet valve comprises a ported disc 14 which is rotatable by a flow actuated device, not shown, through tie-rods 15. The main inlet valve communicates with a casing 16 which is attached to the exterior of the stand-pipe and forms a vertical duct 17 which communicates at 18 with the stand-pipe, the orifice 18 being located just above the lowest level reached by the liquid column in operation. Inlet valves controlled by flow-actuated paddles are themselves known. In the present case p the inlet valve 14 is of the semi-rotary type,

and the tie-rod 15 couples the valve with a flow-actuated paddle situated at the lower end of the stand pipe 10,01 in the conduit with which that stand pipe communicates.

Thus on movement of the column in one direction, the flow-actuated paddle is moved in a corresponding direction and the semirotary valve 14; is open or closed.

' The exhaust valve 12 is of the known type .adapted to open on reduction of pressure within the stand pipe and to be closed by impact upon the rising liquid column on the compression stroke. If desired a spring (not shown) may be provided to assist in opening the valve 12.

The stand-pipe is provided with three butterfly valves 19 arranged one above the other to open communication between the duct 17 and the working cylinder. Each valve, which is pivoted to turn about a point 20, is provided with a projecting arm 21 which is coupled by a tie-rod 22 to a lever 23, each lever carrying upon its outer end a float 24. The operation of the valves is as follows Upon the explosion stroke the column of water or other fluid in the stand-pipe 10 is driven downwards and due to its momentum a partial vacuum is established in the combustion chamber. At or about this time the inlet valve 11 is opened and a supply of fresh fuel forced into the duct 17. The supply of fuel may be effected under pressure either by an external compressor or by the oscillation of a column of liquid within a separate chamber or by vacuum or by other means. The surface of the liquid column having fallen below the orifice 18, the combustible charge passes from the duct 17 through this orifice into the working cylinder. Upon the return flow of the liquid the orifice 18 is submerged but at the same time the lower float 24: is raised to open the lowermost of the butterfly valves 19.

In a similar manner when the rising liquid column reaches such a level as to submerge the lowermost butterfly valve, the float 24 of the valve next above it is raised and so each valve is opened in turn and the charge is introduced into a zone immediately above and rising bodily with the surface of the liquid column. During practically the whole of the return stroke the exhaust valve 12 is open and the exhaust gases are expelled through it. the combustible charge being prevented from flowing out through the exhaust valve by the partition 13. At or about the time when the highest butterfly valve 19 becomes submerged the main inlet valve 11 and the exhaust valve 12 are closed. Further upward motion of the liquid column compresses the combustible charge which is then exploded and the cycle of operations repeated.

In order to prevent the butterfly valves being damaged by a possible back-fire or premature explosion within the duct 17, a spring-loaded relief valve 26 is located between the duct and the working cylinder. This valve is arranged to open upon the pressure within the duct 17 exceeding that within the working cylinder. In order to prevent the formation of a partial vacuum within the duct 17 at the end of the explosion stroke a non-return valve 27 communicating with the working cylinder by a pipe is placed in the top of the casing 16, or valve 27 may communicate direct with the atmosphere. The Valve 27 is arranged to open upon the pressure withinthe working cylinder or of the atmosphere becoming greater than the pressure within the duct 17 In the modified construction shown in Figure 2, five butterfly valves 19 are arraanged to communicate between the duct 17 and the working cylinder. Each valve, which is pivoted for movement about a point 20, is formed with a lever 28 which projects into the working cylinder, and carries upon its free end a float or paddle 29. Each lever 2'8 is downwardly inclined at such an angle that the float or paddle carried by it is lifted by the rising liquid column immediately after the valve below has been sub merged.

The bottom 18 of the duct 17 may coincide with the lowest level reached by the liquid piston, or any other means may, if desired, be adopted to admit fuel at the end of the outward stroke.

I claim V 1. In a liquid piston internal combustion pump in which the fuel charge is introduced wholly or in part during the upstroke of the liquid column, the combination of a pump chamber and guide mechanism within the pump chamber operable by the liquid piston, to confine the distribution of the charge to a zone which is immediately above and rises bodily with the surface of said liquid piston.

2. In a liquid piston internal combustion pump the combination of a pump chamber, a duct on the exterior of the chamber for fuel gas, a series of distributing valves mounted one above the other in the wall of the chamber to communicate between the interior thereof and the duct aforesaid, and means for opening and closing each valve in sequence from the bottom in step with the rise of the liquid piston.

3. In a liquid piston internal combustion pump the combination of a pump chamber, a duct on the exterior of the chamber for fuel gas, a series of distributing valves mounted one above the other in the wall of the chamber to communicate between the interior thereof and the duct aforesaid, and means, operable during the rise of the liquid piston, to ensure that only that valve which is situated substantially at the surface level thereof is open.

4. In a liquid piston internal combustion pump the combination of a pump chamber, a duct on the exterior of the chamber for fuel gas, a series of distributing valves mounted one above the other in the wall of the chamber to communicate between the interior thereof and the duct aforesaid, means to bias the valves towards the closed position, and means for opening the valves in sequence duringrthe rise of liquid piston, comprising for each welve .a float a or which :pmjects. into. the interior: cf the; chamber. i T .-3 i

Ina liquid piston: internail combustion pump which thefufel charge is: intro duced wholly :or' in part acluring'the upstroke. of-the Yliquid column, the combination of &- paunpv chamber, a I duct upon the exterior. of the chamber for fuel; gas; a of =bwttervalves; mounted. one abovefthe other the wall of the chamber :cbmmunicating between the interior" thereof and the duct aforesaid, means: to bias the; valves towards the closed "position, and means for-opening; the valves in sequence during the rise of; the; liquid pistomcomprising' for each. valmwt: float or paddle which projects into ante-- ricr of the chamber. u

6.. Inaliquid piston internalcomibustion ump the combination .of' a 1 pump chamber a duct upon the exterior of the chamber for gaseous fuel, a series of butterfly: 'vailvcs within the: chamber wall each mounted upon a horizontal spindle and one above the other to communicate with the interior of the chamber and. the duct aforesaid, for each valve .a' pivoted arm connected 'thereto'raind projectingintqthe. interior of the. pump chamber,.and affloat upon the free; endmof each said arm.

I. In a liquid piston internalcombustion pump the combination of a frpulnp chamber, a duct upon the exterior of the chamber for gaseous fuel, a series of butterfly valves within the chamber wall each mounted upon a horizontal spindle and one above the other to communicate with the interior of the chamber and the duct aforesaid, for each valve a pivoted arm connected thereto and projecting into the interior of the pump chamber, and a float upon the free end of each said arm,the said butterfly valves being so spaced apart that about thetime that one valve is submerged by the rising liquid piston the piston comes into contact with, and lifts, the float associated with the next higher valve.

8. In a liquid piston internal combustion pump the combination of a pump chamber, a duct upon the exterior of the chamber for gaseous fuel, a series of butterfly valves Within the chamber wall each mounted upon a horizontal spindle and one above the other to communicate between the interior of the chamber and the duct aforesaid, for each valve a pivoted arm connected thereto and projecting into the interior of the pump chamber, and a float upon the free end of each of the said arms, each float being approximately level with the top of the valve immediately below.

9. In a liquid piston internal combustion pump the combination of a pump chamber, a duct upon the exterior of the chamber for gaseous fuel, a series of butterfly "alves each mounted upon a horizontal spindle, one above the other within the chamber Wall to communicate between the interior of the 5 chamber and the duct aforesaid, an arm projecting from each butterfly valve into the interior of the pump chamber and a float upon the free end of each of the said arms. The combination with apparatus ac- 10 cording to claim 4: of two relief valves for equalizing the gas pressure in the pump chamber and the duct.

11. In a liquid piston internal combustion pump in which the fuel charge is introduced wholly or in part during the upstroke of the liquid column, the combination of a pump chamber, and guide mechanism within the pump chamber, controlled by the liquid 7 piston, to confine the distribution of the charge to a zone which is immediately above and rises bodily with the surface of said liquid piston.

12. In a liquid piston internal combustion pump in which the fuel charge is introduced wholly or in part during the upstroke of the liquid column, the combination of a pump chamber, and guide mechanism within the pump chamber, to confine the distribution of the charge to a zone which is immediately above and rises bodily with the surface of said liquid piston.

In testimony whereof I affix my signature.

STANLEY PERCY CHRISTIE. 

